In general, semiconductor apparatuses, such as a processor and a memory device, are implemented with integrated circuits and used in various types of electronic devices such as a desktop computer, a laptop computer, a mobile phone, an electronic scheduler, a portable audio player, a camera, and a smart phone. Semiconductor apparatuses have gradually reduced in size, their operation speed has increased, and their power consumption has decreased.
A semiconductor apparatus may perform data communication while exchanging signals. Thus, the performance of the semiconductor apparatus may be determined by how precisely signals are transmitted and received. However, the miniaturization, the high-speed operation, and the low power consumption of semiconductor apparatuses may make it difficult for the them to precisely transmit and receive signals. Thus, various technologies for precisely transmitting and receiving signals under a severe operating environment have been developed and applied to semiconductor apparatuses.